Various pedestrian detecting technologies have been developed, and have been used in vehicles to detect and remind a driver of pedestrians in the vicinity of a vehicle. Some solutions are based on radar, some solutions are based on multiple cameras, some solutions are based on laser, and some solutions are based on infrared cameras, but these solutions have a same drawback which is high cost. Although some conventional solutions using a single normal camera are low cost, these solutions produce many false positives in order to get high detection rate. Examples of such solutions please see N. Dalal and B. Triggs, “Histograms of Oriented Gradients for Human Detection”, CVPR, 2005; P. Dollar, C. Wojek, B. Schiele and P. Perona, “Pedestrian Detection: An Evaluation of the State of the Art”, PAMI, 2011; D. Geronimo and A. M. Lopez and A. D. Sappa and T Graf “Survey of Pedestrian Detection for Advanced Driver Assistance Systems”, PAMI, 2010; and M. Enzweiler and D. M. Gavrila. Monocular Pedestrian Detection: Survey and Experiments. IEEE Transactions on Pattern Analysis and Machine Intelligence, vol. 31, no. 12, pp. 2179-2195, 2009. In view of the above, there is need to provide a more robust method and system for detecting pedestrians using a single normal camera.